6,145 research outputs found

    Geographical Distribution of Elderly People in Croatia

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    The authors outlined the geographical distribution of individuals displaying longevity in the Republic of Croatia. Elderly people, aged 80 years and older, have been the subject of this study and were viewed in several aspects including the number of elderly people and age-specific mortality rate by districts. Data for the years 1981 and 1991 were reviewed. In 1981 there were 73,052 (1.6%) persons aged 80 or older. Ten years later in 1991 their number had increased to 107,256, which was 2.2% of the whole population. Most of the elderly people live on the islands, in the district of Dubrovnik and in Lika, which is in the continental part of Croatia. There are more women than men among those aged 80 years and older. Age-specific mortality rate in 1981 in Croatia was 170 and in 1991 151 per 1,000 elderly people. In women the rate was 162 in 1981 and 141 in 1991, per 1,000 elderly people. The death rate was higher in men; in 1981 it was 201 and in 1991, 172 per 1,000 elderly people. We can see that the specific mortality rate had fallen in 1991 compared to 1981. The age specific mortality rate varies from district to district. In 1991 the lowest, 110 per 1,000, was in Lika, and the highest in the districts of Vara`din (182 per 1,000), Bjelovar (178 per 1,000) and Zagorje (175 per 1,000). The death rate was higher amongst elderly men (172.31 per 1,000) than elderly women (141.65 per 1,000). The smallest number of those aged 80 years and older with a high death rate is found in Slavonia. The opposite – a high number of elderly people and a low specific mortality rate – can be seen in the district of Lika. On the islands the number of elderly people is high, especially women, and surprisingly, the specific mortality rate is relatively high as well

    Risk groups for clinical complications of norovirus infections: an outbreak investigation.

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    Norovirus infections have been described as self-limiting diseases of short duration. An investigation of a norovirus outbreak in a university hospital provided evidence for severe clinical features in patients with several underlying diseases. Clinical outcomes of norovirus infection were defined. Risk-factor analysis targeting underlying diseases and medication was performed using multivariate analyses. In five outbreak wards, 84 patients and 60 nurses were infected (an overall attack rate of 32% in patients, and 76% in nurses). The causative agent was the new variant Grimsby virus. Severe clinical features, including acute renal failure, arrhythmia and signs of acute graft organ rejection in renal transplant patients, were observed in seven (8.3%) patients. In multivariate analyses, cardiovascular disease (OR 17.1, 95% CI 2.17-403) and renal transplant (OR 13.0, 95% CI 1.63-281) were risk-factors for a potassium decrease of >20%. Age >65 years (OR 11.6, 95% CI 1.89-224) was a risk-factor for diarrhoea lasting >2 days. Immunosuppression (OR 5.7, 95% CI 1.78-20.1) was a risk-factor for a creatinine increase of >10%. Norovirus infections in patients with underlying conditions such as cardiovascular disease, renal transplant and immunosuppressive therapy may lead to severe consequences typified by decreased potassium levels, increased levels of C-reactive protein and creatine phosphokinase. In the elderly, norovirus infection may lead to an increased duration of diarrhoea. Therefore patients at risk should be hospitalised early and monitored frequently. Strict preventional measures should be implemented as early as possible to minimise the risk of nosocomial outbreaks

    Ares-I-X Stability and Control Flight Test: Analysis and Plans

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    The flight test of the Ares I-X vehicle provides a unique opportunity to reduce risk of the design of the Ares I vehicle and test out design, math modeling, and analysis methods. One of the key features of the Ares I design is the significant static aerodynamic instability coupled with the relatively flexible vehicle - potentially resulting in a challenging controls problem to provide adequate flight path performance while also providing adequate structural mode damping and preventing adverse control coupling to the flexible structural modes. Another challenge is to obtain enough data from the single flight to be able to conduct analysis showing the effectiveness of the controls solutions and have data to inform design decisions for Ares I. This paper will outline the modeling approaches and control system design to conduct this flight test, and also the system identification techniques developed to extract key information such as control system performance (gain/phase margins, for example), structural dynamics responses, and aerodynamic model estimations

    NASA's Learn-to-Fly Project Overview

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    Learn-to-Fly (L2F) is an advanced technology development effort aimed at assessing the feasibility of real-time, self-learning flight vehicles. Specifically, research has been conducted on merging real-time aerodynamic modeling, learning adaptive control, and other disciplines with the goal of using this learn to fly methodology to replace the current iterative vehicle development paradigm, substantially reducing the typical ground and flight testing requirements for air vehicle design. Recent activities included an aggressive flight test program with unique fully autonomous fight test vehicles to rapidly advance L2F technology. This paper presents an overview of the project and key components

    Hydration-Scanning Tunneling Microscopy as a Reliable Method for Imaging Biological Specimens and Hydrophilic Insulators

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    The recently discovered high lateral conductivity of molecularly thin adsorbed water films enables investigation of biological specimens, and even of surfaces of hydrophilic insulators by scanning tunneling microscopy (STM). Here we demonstrate the capabilities of this method, which we call hydration-STM (HSTM), with images of various specimens taken in humid atmosphere: We obtained images of a glass coverslip, collagen molecules, tobacco mosaic virus, lipid bilayers and cryosectioned bovine achilles tendon on mica. To elucidate the physical mechanism of this conduction phenomenon we recorded current-voltage curves on hydrated mica. This revealed a basically ohmic behavior of the J-V curves without a threshold voltage to activate the current transport and indicates that electrochemistry probably does not dominate the surface conductivity. We assume that the conduction mechanism is due to structuring of water at the surface
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